Locking ring for store arming device

ABSTRACT

A SAFETY LOCKING RING FOR A STORE HAVING A REENTRANT LIP ON ONE OF ITS ENDS TO WHICH IS HELD A DETACHABLE INSERT CAP HAVING A PLURALITY OF SPACED, RESILIENT, MOVABLE ARMS THE RING HAS A PLURALITY OF FINGERS WHICH EXTEND INTO THE SPACES BETWEEN THE CAP ARMS TO ENGAGE THE ARMS AND PREVENT THEIR INWARD MOVEMENT AND DETACHMENT OF THE FROM THE STORE WHEN THE RING IS IN A FIRST POSITION.

Oct. 5, 1971 M. N. MILLER 3,610,092

I LOCKING RING FOR STORE ARMING DEVICE Filed Nov. 29 1968 2 Sheets-Sheet1 ,FIG. 1

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LOCKING RING FOR STORE ARMING DEVICE Filed Nov. 29, 1968 2 Sheets-ShootI f 22 y 2 2o- A FIG. 3

INVENTOR MATTHEW N. MILLER ATTORNEYS United States Patent i 3,610,092LOCKING RING FOR STORE ARMING DEVICE Matthew N. Miller, Topanga, Califi,assignor to Fair-child Industries, Inc., Germantown, Md. Filed Nov. 29,1968, Ser. No. 780,077 Int. Cl. F41f /02 US. Cl. 89-15 D 9 ClaimsABSTRACT OF THE DISCLOSURE In my co-pending application Ser. No. 585,996entitled Store Launching System, filed Sept. 1, 1966, now US. Pat. No.3,435,725, and assigned to the same assignee, a system is disclosed forlaunching stores, such as pyrotechnic devices, from an aircraft. In thesystem of that application a store having a re-entrant lip at its upperend has a plastic insert cap fitted therein. The cap has a centralflange and a plurality of separate radially resilient arms with enlargedportions on the outer surfaces of the bottom portions of the armsdepending downwardly from the flange. The enlarged portions of theresilient arms are snapped into the upper end of the store to engage andbe held by the re-entrant lip. A lanyard for arming the store isconnected between the cap and a fuse mechanism, or other similaractuating device, on the store.

As another component of the system of the foregoing application, alaunch tube is provided with a plurality of fingers which extend intothe tube. As the store is launched down the tube, the fingers grasp theflange on the cap and hold it, causing the resilient arms to moveinwardly and break their engagement with the stores re-entrant lip. Thecap is held by the fingers of the launch tube as the store leaves thetube so that the lanyard is pulled and the store is actuated.

The present invention relates to a store of the aforesaid type whichuses an insert cap and more particularly to a safety device whichprevents accidental removal of the cap and thereby accidental arming ofthe store. In accordance with the invention the safety device comprisesa locking ring having a flanged portion from which depends downwardly anumber of fingers which fit in the spaces between the arms of the insertcap. When located in a first, or safety position adjacent the top of thestore re-entrant lip, the safety ring prevents the resilient arms of thecap from moving inwardly to a point where they can become disengagedfrom the re-entrant lip. This prevents arming of the store. When thelocking ring is moved to a second position adjacent the cap flange, thecap arms can clear the fingers of the locking ring and move radiallyinward to a position where the cap can be detached from the store.

It is therefore an object of the present invention to provide a. safetylocking ring for a store of the type having a detachable insert cap.

Another object is to provide a safety locking ring for the detachableinsert cap of a store in which the resilient arms of the insert cap areprevented from moving inwardly to a point where they can be detachedfrom the store when the locking ring is in a first position.

Another object is to provide a locking ring for the insert cap of astore in which the locking ring has a flange and a plurality ofdownwardly depending fingers, the

3,610,092 Patented Oct. 5, 1971 fingers preventing the cap from beingaccidentally detached from the store when the locking ring is in a firstposition, the flange of the ring adapted to be grasped by the fingers ofa launching tube and moved to a second position when the store islaunched to permit the cap to be detached.

Other objects and advantages of the present invention will become moreapparent upon reference to the following specification and annexeddrawings, in which:

FIG. 1 is an elevational view of a portion of a store with an attachedinsert cap and locking ring shown partially in section and partiallybroken away;

'FIG. 2 is an elevational view partly in section, showing a portion of astore and a portion of a launch tube and demonstrating the action of thelocking ring;

FIG. 3 is a fragmentary cross-sectional view of a portion of anassembled store, cap and locking ring with the locking ring in thesafety position;

FIG. 4 is a top view taken in cross-section along lines 4-4 of FIG. 1,showing the cap and ring assembled to a store with the ring in thesafety position; and

FIG. 5 is a top view taken in cross-section along lines 55 of FIG. 2,showing the locking ring in a second position, permitting detachment ofthe cap from the store.

Referring to FIGS. 1 and 2, the upper portion of a store 10 is shownwhich comprises a casing filled with any suitable material such as anexplosive or a pyrotechnic chemical. The upper end of the store housing'10 has an inwardly bent or re-entrant lip 12 at the upper end of aportion of the casing which extends above the top 14 of the filledsection of the casing. An actuating device, such as a fuse 16, islocated on the top of the filled section of the body.

A detachable insert cap 20 is shown in FIGS. 1 and 2 associated with thestore 10. Insert cap 20 is of a generally tubular overall shape and hasan upper outwardly extending flange 22 below which and from whichdepends downwardly a cylindrically shaped segment 23 whose outerdiameter is less than the outer diameter of flange 22. A plurality ofarms 24 extend downwardly from the closed segment 23. The upper portionof each of the arms is of the same diameter as the segment 23 While thelower portion has an enlarged diameter portion 26 with chamfered upperand lower edges 28 and 29. There is a space between two adjacentdownwardly depending arms 24. The insert cap 20 is made of a suitablematerial such as plastic so that the arms 24 are radially resilient. Theentire cap can be molded in one operation by any suitable process.

As shown in FIG. 1, the insert cap 20 is held within the top section ofthe casing of store 10. A lanyard (not shown) is connected between theactuating mechanism 16 on the store body and a fixed point on the cap.This is described in greater detail in the aforesaid co-pendingapplication. When the cap is separated from the store by a distanceslightly in excess of the lanyard length and the cap held to a fixedpoint, the lanyard will be pulled and the store will be armed.

Considering the attachment of the cap to the store without the use ofthe safety locking ring, this is accom' plished by pushing the capdownwardly so that the arms 24 move radially inward until their enlargedsections 26 fit within the re-entrant lip 12. At this time the arms 24expand radially outwardly so that the enlarged portions 26 thereof abutthe inside of the store housing 10 and the re-entrant lip 12 locks onthe chamfered upper edge 28. The cap can be separated from the store bygrasping the top flange 22 and pulling it upwardly. This causes theupper chamfered edges 28 of the arms 24 to ride over the re-entrant lipand the arms 24 to be moved radially inwardly. This breaks theengagement between the arms and the re-entrant lip 12. If the upwardforce is maintained, eventually the cap is pulled completely out of thestore carrying with it the lanyard. If the cap is moved far enough withrespect to the store, the lanyard pull will arm the store.

As should be apparent from a description of the manner by which the capcan be detached, it is desirable that some safety arrangement beprovided so that the insert cap cannot be removed accidentally from thestore to arm it. Such accidental removal can occur, for example, whenthe store is located in an area available to personnel who are moving orloading the stores. Here there might be a tendency to pick up the storeby the cap rather than by its body. This gives rise to the possibilityof detaching the cap and accidentally arming the store.

To prevent accidental arming of the store, a locking ring is provided.The locking ring 30 has an upper outwardly extending flange 32. Aplurality of fingers 34 depend downwardly from the inner edge of theflange and are spaced therearound. It is preferred that the entirelocking ring 30 be made of a rigid material, such as metal, so that thefingers 34 are not radially movable. As shown in FIGS. 1 through 5, thefingers 34 of the locking ring are spaced around the flange 32 and areof such a size that they fit within the spaces between the arms 24 ofthe cap 20.

As shown best in FIG. 3, each of the fingers 34 of the locking ring hasa generally S-shape with the S being laid on its side. The upper leg 34alies outwardly of the minimum outer diameter segment 23 of the cap sothat it can clear this portion when moved upwardly toward the cap flange22. The lower leg 34b of each finger 34 lies inwardly of the outerdiameter of the enlarged portions 26 of two adjacent arms 24. The twolegs 34a and 34b are joined by a small center leg 340.

To assemble a locking ring 30 to a cap 20, it is only necessary to takethe cap and push its arms 24 through the opening of the flange ring 32.The cap and the locking ring are aligned so the fingers 34 will be inthe spaces between the cap arms 24 as shown in FIGS. 1 and 2.

To attach the assembly of the cap and locking ring to the store, thering is pushed up on the cap as far as possible. The leg 34a of thefingers clear the cap segment 23. With the ring in this position, theresilient arms 24 of the cap are free to be moved radially inwardly, toclear the lip 12. It should be understood that in an inward radialmovement of an arm 24, that its lower end will move farther inward thanany other point on the arm. Thus, the cap can be forced down into thestore casing opening defined by the re-entrant lip 12 and the cap arms24 will snap into position to lock the cap-ring assembly to the store inthe manner previously described for the cap alone.

After the assembly is fastened to the store, the locking ring 30 ispushed downward as far as possible to the safety position. This is shownin FIGS. 1 and 3. With the ring in the safety position the ends of itsfingers contact the top 14 of the store. If an upward force is exertedon the cap 20, the arms 24 thereof will initially begin to deflectradially inwardly. However, after a small initial movement the inneredges of the enlarged portions 26 of the arms 24 will engage the fingers34 of the locking ring 30 and further inward movement of the arms 24 isprevented. The widths of the locking ring fingers 34 are selected withrespect to the spaces between the cap arms 24 so that the cap armsengage the fingers and prevented from further inward movement at a pointbefore their enlarged portions 26 can clear the re-entrant lip 12. FIG.4 shows the cap and ring in cross-section and it can be seen that therewill only be a slight radially inward deflection of the arms 24 beforethey engage the rigid fingers 34 of the locking ring. Since the cap armscannot clear the lip 12, the cap is locked to the store.

To disengage the cap-ring assembly from the store, it is only necessaryto move the cap to the upward or release position which is shown in FIG.2. With the ring in the upward, or release, position the upper leg 34aof each finger 34 clears the cap segment 23 so that the ring flange 32can come near to or abut the cap flange 22. With the locking ring 30 inthis position the arms 24 of the cap are free to move radially inward bya sufiicient distance where they can clear the re-entrant lip 12 beforeengaging the fingers of the locking ring. This is shown in FIG. 5. Thus,as should be apparent from the foregoing description, the only Way thatthe cap can be removed from the store to arm it is to first pull thelocking ring 30 up to a position where its flange is adjacent the flange22 of the cap 20.

FIG. 2 shows the cap and ring assembly used in a launching system of thetype described in the aforementioned patent application. A launchingtube 60 is provided having a number of openings 62 spaced around itsperiphery. There are usually three or four of these openings. Aspring-loaded gripping finger 64 is mounted on a suitable bracket 66about a pivot 68. A spring 70 is placed around the pivot 68. The springhas extending arms one of which 71 engages the tube and the other ofwhich 73 engages a point on the gripping finger 64. Each of the grippingfingers 64 is biased inwardly into the interior of the launching tube bythe spring 70.

Each of the gripping fingers 60 has a shoulder portion 74 which isnormally located in the tube, and a hook 76 at its end. In operation ofthe launching system the store 10 is launched down the tube (from theupper portion of the tube as shown in FIG. 2). The locking ring is inits safety (down) position during launch, as shown in FIG. 1. As thestore moves down the launch tube the shoulder 74 of each gripping finger64 rides on the outer casing 10 of the store, thereby keeping its hook76 cleared of the store.

When the shoulder 74 of a gripping finger falls into the space betweenthe cap flange 22 and the flange locking ring 32, the gripping fingerswill move in. The hooks 76 of the gripping fingers will first catch theunderside of the locking ring flange 32. As the store continues itstravel down the tube, the locking ring is pulled upwardly into itsrelease position where the arms 24 are free to move inwardly to aposition to detach the cap from the store. Continued further movement ofthe store down the tube causes the cap arms 24 to move inwardly sincethe locking ring has reached its upward travel limit and it and the capare held by the gripping fingers 64. Thus, the

arms 24 of the cap 20 are moved inwardly by the movement of the store toa position where they finally disengage the cap from the store. As thestore moves further down the tube and out of the tube, the cap is held.As it moves a distance slightly greater than that of the length of thelanyard, the store is armed. The length of the lanyard is usuallyselected so that the store will not be armed until it clears theaircraft.

The cap-ring assembly is held by the gripping fingers 64 until the nextstore is launched. The leading edge of the store casing engages theshoulders 74 of the gripping fingers 64 causing the fingers to moveoutwardly so that the hooks 76 clear the locking ring flange 32. Thestore being launched pushes the cap-ring assembly out of the tube aheadof it. It should be understood that the store can be launched from aninclined or horizontal position by gravity or under pressure, ifdesired.

As can be seen, a novel and simple locking ring has been provided whichprevents the accidental actuation of a store by the removal of an insertcap to which a lanyard is attached.

While the preferred embodiment of the invention has been describedabove, it will be understood that this is illustrative only, and theinvention is limited solely by the appended claims.

What is claimed:

1. In combination, a first member having a plurality of resilient armswhich depend from a common portion of said first member and havingspaces between the free ends of said arms, said arms being normally freeto move radially inwardly, a locking ring of substantially rigidmaterial having a central member which is generally concentric with saidfirst member and is movable longitudinally relative thereto between afirst and a second position, said locking ring having a plurality offingers depending from its central member each being of a shape and sizeto fit in a respective space between two of the arms of said firstmember, each of said fingers having a first portion the distance towhose inner wall as measured from the center of the ring is greater thanthe distance to the inner wall of another portion of the finger which ismore closely adjacent the free end of the arm of said first member, saidlocking ring when in said first position having its fingers locatedadjacent the free ends of the arms of said first member to engage thearms upon radially inward movement thereof, and said locking ring whenin said second position locating the fingers more remotely from the freeends of the arms to permit further radially inward movement of said armsthan when said locking ring is in said first position.

2. The combination of claim 1 wherein the overall height of said lockingring and the height of its fingers are less than the height of the armsof said first member thereby permitting the locking ring to be movedrelative to said arms from said first position where the ends of itsfingers are near the bottom ends of the arms of said first member tosaid second position where the ends of the locking ring fingers areabove the bottom ends of said arms, the width of the locking ringfingers being of a size to engage said arms and prevent radial inwardmotion thereof beyond a predetermined distance.

3. The combination of claim 2 wherein the fingers of the locking ringare formed -with an upper portion which can clear the outer surface ofthe first member when the locking ring is moved to said second position,the lower portion of each finger lying within the space between twoadjacent arms of the first member.

4. The combination of claim 2 wherein said first member and said lockingring are of generally circular shape and have a common central axis.

5. The combination of claim 1 wherein said other portion of each saidfinger lies entirely within the area of the inner and outer surfaces ofthe respective arms adjacent each finger.

6. The combination of claim 5 wherein each of said arms has its lowerfree end portion of enlarged thickness as compared to the upper portionof the arm which is adjacent to the common portion of said first member,

7. In combination a store having a housing with an inwardly extendingholding means surrounding an open portion, an insert cap having aplurality of radially resilient spaced arms which depend from a commonmember, a locking ring having a plurality of fingers depending from acentral member and being of a shape and size to fit within the spacesbetween the arms of the insert cap, the central member of said ringfitting around the outside of the arms of said cap and the overallheight of said locking ring and the height of its fingers being lessthan the height of the cap arms thereby permitting the locking ring tobe moved on said insert cap from a first position where the ends of itsfingers are near the free ends of the cap arms to a second positionwhere the ends of the locking ring fingers are above the free ends ofthe cap arms, the width of the locking ring fingers being of a size toengage the free ends of the cap arms and prevent radial inward motionthereof beyond a predetermined distance the outer diameter of the insertcap across said arms in the area where said insert cap moves from saidfirst to said second position being less than the diameter of theremaining portion of the arms below said first position, the arms ofsaid insert cap fitting within the store housing and the insert capbeing held to said holding means of said store housing by the enlargedlower portions thereof which engage said holding means.

8. The combination of claim 7 wherein said locking ring central membercomprises a ring flange, said ring flange when in a first position whichplaces the bottom of its fingers adjacent the bottom of the cap armspreventing inward movement of the arms beyond a predetermined pointwhich prevents removal of the cap from the store.

9. The combination of claim 8 wherein said locking ring when movedtoward the central member of the insert cap permits inward movement ofthe cap arms to a point where they can detach from the holding means.

References Cited UNITED STATES PATENTS 2,485,763 10/1949 Moon 285862,928,319 3/1960 Sokolowski 89-l (.01) 3,435,725 4/1969 Miller 89-1.5

SAMUEL W. ENGLE, Primary Examiner US. Cl. X.R. 285-86

